“The big news is that we are expecting our rainbow baby. This baby is our rainbow after the storm. I’m super excited,” Lowell, who teased an upcoming announcement on Instagram in August, tells Us Weekly exclusively. “It was a huge shock at first. We were not planning it, especially after the miscarriage and how I went downhill with my mental illness.”

She added: “We were going to wait a really long time. We were using protection and everything and still got pregnant. This baby just wanted to be here. It was very unexpected.”

Lowell, 26, and Baltierra, also 26, are parents of 3-year-old daughter, Novalee. The middle-school sweethearts, who tied the knot in August 2015, placed their eldest daughter, Carly, now 9, for adoption in 2009. The ups and downs of their open adoption are documented on the hit MTV docuseries.

The MTV personality previously announced she was pregnant on a January episode of Teen Mom OG. The couple, however, revealed during the February 26 episode of the show that Lowell had a miscarriage. Lowell, who had battled with postpartum depression after giving birth to Novalee in 2015, entered treatment again in January after the miscarriage because she was having suicidal thoughts.

Lowell and Baltierra also fought back against split rumors earlier this year. After the Conquering Chaos author changed her Instagram name from “Catelynn Baltierra” to “Catelynn Lowell” in May, fans started to wonder if the duo had called it quits. Lowell exclusively told Us Weekly at the time that there was no truth to the divorce rumors.

“Tyler and I are not getting a divorce. Couples go through ups and downs. That’s normal life,” she said in a statement to Us on May 15. “We are a solid couple that will work through anything life throws at us.”

Teen Mom OG returns to MTV on Monday, October 1.

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